Superconducting Surface Impedance under Radiofrequency Field

Based on BCS theory with moving Cooper pairs, the electron states distribution at 0K and the probability of electron occupation with finite temperature have been derived and applied to anomalous skin effect theory to obtain the surface impedance of a superconductor under radiofrequency (RF) field. We present the numerical results for Nb and compare these with representative RF field-dependent effective surface resistance measurements from a 1.5 GHz resonant structure

Dynamical instabilities of Bose-Einstein condensates at the band-edge in one-dimensional optical lattices

We report on experiments that demonstrate dynamical instability in a Bose-Einstein condensate at the band-edge of a one-dimensional optical lattice. The instability manifests as rapid depletion of the condensate and conversion to a thermal cloud. We consider the collisional processes that can occur in such a system, and perform numerical modeling of the experiments using both a mean-field and beyond mean-field approach. We compare our numerical results to the experimental data, and find that the Gross-Pitaevskii equation is not able to describe this experiment. Our beyond mean-field approach, known as the truncated Wigner method, allows us to make quantitative predictions for the processes of parametric growth and thermalization that are observed in the laboratory, and we find good agreement with the experimental results.Comment: v2: Added several reference

A rapid bioluminescence assay for measuring ​myeloperoxidase activity in human plasma

Myeloperoxidase (MPO) is a circulating cardiovascular disease (CVD) biomarker used to estimate clinical risk and patient prognosis. Current enzyme-linked immunosorbent assays (ELISA) for MPO concentration are costly and time-intensive. Here we report a novel bioluminescence assay, designated MPO activity on a polymer surface (MAPS), for measuring MPO activity in human plasma samples using the bioluminescent substrate L-012. The method delivers a result in under an hour and is resistant to confounding effects from endogenous MPO inhibitors. In a pilot clinical study, we compared MAPS and two clinical ELISAs using 72 plasma samples from cardiac catheterization patients. Results from parallel MAPS and ELISAs were concordant within 2±11 μg l(−1) MPO with similar uncertainty and reproducibility. Results between parallel MAPS and ELISA were in better agreement than those between independent ELISAs. MAPS may provide an inexpensive and rapid assay for determining MPO activity in plasma samples from patients with CVD or potentially other immune and inflammatory disorders

Using Geospatial Information Technologies to Identify Factors Affecting Grazing Distribution on Grasslands

The relationship between environmental and management factors and grazing livestock distribution is fundamental to understanding and improving grazing systems. With the advent of geospatial information technologies, global positioning systems (GPS) and geographic information systems (GIS) have been used to improve the efficiency and effectiveness of quantifying the distribution of livestock grazing in response to various independent variables (Bailey et al., 2001). The specific objective of this project was to develop a tool that enables managers and students to identify and study the effect of management and environmental factors on grazing livestock distribution

Effect of Summer Grazing on Crude Protein and Digestibility of Winter Diets of Cattle in the Nebraska Sandhills

Twenty-one pastures (three pastures/ treatment) were used in a two-year study to determine the effects of summer grazing on winter diet quality of Sandhills range. Summer grazing treatments consisted of no summer grazing (control) and June or July grazing at three stocking rates. After summer grazing, pastures were then diet sampled using esophageally fistulated cows in November, January and March following summer treatments. Year and sampling date had a significant effect on CP and IVDMD of winter range diets, whereas summer grazing treatments did not have a large impact

Usage, adherence and attrition: how new mothers engage with a nurse-moderated web-based intervention to support maternal and infant health. A 9-month observational study

Objectives: To identify factors predicting use, adherence and attrition with a nurse-moderated webbased group intervention designed to support mothers of infants aged 0–6 months. Design: 9-Month observational study. Setting: Community maternal and child health service. Participants: 240 mothers attending initial postnatal health checks at community clinics who were randomly assigned to the intervention arm of a pragmatic preference randomised trial (total randomised controlled trial, n=819; response rate=45%). Intervention: In the first week (phase I), mothers were assisted with their first website login by a research assistant. In weeks 2–7 (phase II), mothers participated in the web-based intervention with an expectation of weekly logins. The web-based intervention was comparable to traditional face-to-face new mothers’ groups. During weeks 8–26 (phase III), mothers participated in an extended programme at a frequency of their choosing. Primary outcome measures: Number of logins and posted messages. Standard self-report measures assessed maternal demographic and psychosocial characteristics. Results: In phase II, the median number of logins was 9 logins (IQR=1–25), and in phase III, it was 10 logins (IQR=0–39). Incident risk ratios from multivariable analyses indicated that compared to mothers with the lowest third of logins in phase I, those with the highest third had 6.43 times as many logins in phase II and 7.14 times in phase III. Fifty per cent of mothers logged-in at least once every 30 days for 147 days after phase I and 44% logged-in at least once in the last 30 days of the intervention. Frequency of logins during phase I was a stronger predictor of mothers’ level of engagement with the intervention than their demographic and psychosocial characteristics. Conclusions: Mothers’ early use of web-based interventions could be employed to customise engagement protocols to the circumstances of individual mothers with the aim of improving adherence and reducing attrition with web-based interventions.Michael G Sawyer, Christy E Reece, Kerrie Bowering, Debra Jeffs, Alyssa C P Sawyer, Jacqueline D Peters, Christine Mpundu-Kaambwa, Jennifer J Clark, Denise McDonald, Murthy N Mittinty, John W Lync

Toward a Systematic Holographic QCD: A Braneless Approach

Recently a holographic model of hadrons motivated by AdS/CFT has been proposed to fit the low energy data of mesons. We point out that the infrared physics can be developed in a more systematic manner by exploiting backreaction of the nonperturbative condensates. We show that these condensates can naturally provide the IR cutoff corresponding to confinement, thus removing some of the ambiguities from the original formulation of the model. We also show how asymptotic freedom can be incorporated into the theory, and the substantial effect it has on the glueball spectrum and gluon condensate of the theory. A simple reinterpretation of the holographic scale results in a non-perturbative running for alpha_s which remains finite for all energies. We also find the leading effects of adding the higher condensate into the theory. The difficulties for such models to reproduce the proper Regge physics lead us to speculate about extensions of our model incorporating tachyon condensation.Comment: 27 pages, LaTe